In recent years, as the resolutions of solid-state imaging components such as charge coupled device (CCD) area sensors, complementary metal oxide semiconductor (CMOS) image sensors and the like have risen, the demand for information systems with imaging functions such as digital electronic still cameras, digital video cameras, portable telephones, personal digital assistants (PDAs, which are portable information terminals) and the like has been rapidly increasing. The above-mentioned information devices with imaging functions are referred to herein as “imaging devices”.
Heretofore, by processing that synthesizes plural images captured by focus bracket imaging, in which successive images are captured with the focus position being altered, it has become possible to obtain an image in which blurring is controlled or a fully focused image in which the whole of the image is in focus or the like. However, in this synthesis processing, the degree of correlation between images used in the processing may fall if there is blurring due to hand movement and/or blurring due to subject movement between the successive image captures, and an intended image may not be obtained.
As a technology for solving this problem, Patent Document 1 (Japanese Patent Application Laid-Open (JP-A) No. 2008-271240) discloses an imaging device that is provided with a focus bracket imaging unit, a corresponding point detection unit, an image deformation unit, an image synthesis unit and a recording unit. The focus bracket imaging unit obtains plural images by moving a focus point discretely in pre-specified movement amounts and capturing successive images. The corresponding point detection unit detects corresponding points of subjects in the plural images captured by the focus bracket imaging unit. The image deformation unit deforms the plural images, except for a single reference image selected from the plural images by a predetermined criterion, such that the positions of the corresponding points in the plural images match up with the reference image. The image synthesis unit synthesizes the plural images, including the deformed images. The recording unit records an image obtained by the image synthesis unit at a recording medium.